Does fall in platelets and WBC indicate weak immune system?

I am a 30 years old male whose complete blood counts (CBC) has fallen for the last three months. The platelets fell from around 2,40,000 to 1,60,000, white blood cell (WBC) fell from 7500 to around 5500. On the other hand RBC, haemoglobin and lymphocytes has increased. Does fall in platelets and WBC indicate a weak immune system?